NP
Nonlinear Processes in Geosciences

Global warming

El Niño is back: What it Means for Global Warming?

March 16, 2023
El Niño is back: What it Means for Global Warming?
El Niño vs la Niña schematic representation of wind anomalies (arrows) and ocean temperature anomalies (colors). source: https://thecolumn.ahacentre.org/insight/vol-66-getting-to-know-el-nino-la-nina/

The World Meteorological Organization (WMO) has just announced that the La Niña episode has officially ended, and from autumn onwards, it should give way to an El Niño phase. But what does that mean? And what is the influence of these weather phenomena on global warming?For those who have never heard of La Niña before, here’s an explanation of this phenomenon. The Earth rotates, so there are ...[Read More]

Sea level rise: a global threat in a warming planet

and February 28, 2023
Sea level rise: a global threat in a warming planet
Credit: Marco Anzidei

Over 70% of the Earth’s surface is covered by seas and oceans but in the geological past the extension of sea and land has varied several times as sea level changed over time. During the past millions of years, the oceans have cyclically retreated and expanded with the alternating of warmer and colder climatic periods in consequence of the astronomical motions of the Earth, repeatedly changi ...[Read More]

NP Interview: Federico Grazzini on Climate Change casts shadows on the present and the future of the Mediterranean Basin

November 17, 2022
NP Interview: Federico Grazzini on Climate Change casts shadows on the present and the future of the Mediterranean Basin
Monthly mean sea surface temperature averaged over western and central Mediterranean sea [0E - 22E], months April - November. The blue line corresponds to the recent climatology 1991-2020 with the shading respectively showing 1,2,3 standard deviations of the monthly averages from the mean. Symbols are showing this year values and, for comparison with a previous strongest marine heat wave, the values recorded in 2003.

Weather extreme events in the year 2022 are really hitting the  Mediterranean basin very hard. Since the beginning of the year we are observing a widespread drought, heatwaves but also severe thunderstorms. Few days before the COP meeting in Sharm-el-sheik we discussed one of the experts of Mediterranean climate, Federico Grazzini, to unveil whether these events can be linked to climate change. Fe ...[Read More]

What the 2022 summer thunderstorms in the Mediterranean tell us about the ongoing climate change?

September 7, 2022
What the 2022 summer thunderstorms in the Mediterranean tell us about the ongoing climate change?
Lightning trace from 00 UTC to 18 UTC on 18 July 2022 showing the derecho track (dark red to white). Source: https://www.blitzortung.org/it/live_lightning_maps.php

The 2022 European summer was governed by the presence of a persistent cold drop (low pressure area) located between Portugal and France. The change in its position has determined the alternation between hot conditions (low pressure center over Portugal) and stormy conditions (cold drop over France). The warming of the Mediterranean Sea (up to +6°C compared to the period 1990-2020) has largely cont ...[Read More]